SLHS 1301 The Physics and Biology of Spoken Language. Practice Exam 2. b) 2 32

Transcription

1 SLHS 1301 The Physics and Biology of Spoken Language Practice Exam 2 Chapter 9 1. In analog-to-digital conversion, quantization of the signal means that a) small differences in signal amplitude over time are summed b) small differences in signal amplitude over time are disregarded c) small differences in signal amplitude over time are subtracted d) small differences in signal frequency over time are disregarded 2. An analysis of the waveform for a vowel reveals that the duration of five fundamental periods is 40 ms. What is your best estimate of the fundamental frequency? a) 25 Hz b) 125 Hz c) 250 Hz d) 125 Hz e) Insufficient information to calculate f If sampling frequency (f s ) is 500 Hz, a) f s = 5 khz b) T s = s c) T s = 2 ms d) T s (sampling period) cannot be determined. 4. Which of the following is TRUE? a) A spectrum is a plot of frequency as a function of time. b) A spectrogram is a plot of amplitude as a function of time. c) A waveform is a plot of amplitude as a function of frequency. d) If a signal contains no frequency components above 7 khz, its digitization needs a sampling rate of no less than 14 khz for high quality recording. e) All of the above. 5. Which of the following statements is TRUE? a) Digital signals are always better than analog signals. b) Digital means processing information by using electronic devices. c) A digital filter selectively processes frequency information in a signal. d) Given that human speech has few frequency components above 7 khz, digitization of speech signals needs a sampling rate of at least 3.5 khz for high quality recording. e) All of the above. 6. What is the relationship between bit and byte? a) 1 bit = 1 byte b) 1 bit = 8 bytes c) 1 bit = 1/8 byte d) 1 bit = 10 bytes 7. What are the maximum allocated memory addresses (bytes) in a 32-bit computer? a) 32 billion b) 2 32 c) log 2 32 d)

2 8. If the sampling frequency (Fs) in analog-to-digital conversion = 10,000 Hz, Ts = a).0001 sec b) 1 x 10-4 sec c).1 msec d) all of the above 9. According to Nyquist s sampling theorem a) Fs should be at least ten times higher than the highest frequency of interest b) Fs should be at least two times higher than the highest frequency of interest c) Fs should be equal to the highest frequency of interest d) Fs should be always as high as you can possibly make it 10. Which of the following is False? a) Electronic devices are all digital because they use electricity. b) Digital signal processors typically involve mathematical operations such as amplification, filtering, spectrum analysis, automatic synthesis and recognition. c) If Fs < 2 Fn, aliasing occurs, which causes distortion of the signal. d) Quantization error refers to the difference between the digital signal and the sample values in digital processing. 11. Which of the following does not properly characterize the purposes of speech coding and speech compression? a) To achieve high quality sound at higher sampling rates b) To carry more messages within limited bandwidth c) To optimize signal quality with low sampling rates and limited bandwidth d) To process speech signals for cost-effective communication 12. Which of the following is used in digital speech analysis? a) FFT b) LPC c) Filtering d) All of the above. 13. Which of the following descriptions is false regarding digital spectrum analysis? a) It allows researchers to find out the essential properties of the analyzed signal. b) It allows realtime generation of the spectra and spectrographs of the signal as it is being produced. c) It uses digital to analog conversion. d) It is an integral component of spoken language technology. 14. Which of the following does not use digital technology? a) Dell computers b) Cingular cell phones c) High definition television d) CDs and DVDs e) Cassette-tape answering machine 15. ADC in digital technology stands for. a) Advanced Digital Computing b) Analog to Digital Converter c) Digital to Analog Converter d) Analysis of Direct Current 16. SNR in digital processing stands for a) Signal to Noise Ratio b) Speech to Noise Ratio 2

3 c) Spectrum of Noisy Resonance d) Sampling Noise Reduction Chapter 4 1. If the vocal folds open and close 180 times per second during vowel production, fo of the resulting sound wave is a) dependent on whether the talker is a male or a female b) 125 Hz c) 180 Hz d) none of the above 2. Which of the following cartilages form the larynx? a) hyoid (front), epiglottis (back), cricoid (bottom) b) thyroid (front), arytenoid (back), cricoid (bottom) c) glottis, epiglottis, velum d) hard palate, soft palate, glottis 3. Which of the following statements is TRUE? a) If f0 = 100 Hz, the second formant = 200 Hz. b) The vocal tract serves as a resonator/filter by changing the harmonic amplitudes (not the frequencies) of the buzz sound produced by the vocal folds. c) Voiceless sounds refer to the sounds that we cannot hear. d) All speech sounds are produced by vibrating vocal folds. 4. Which of the following is not a bilabial sound? a) /b/ b) /p/ c) /m/ d) /f/ 5. Production of the phoneme /u/ requires a) raising the front part of the tongue b) lowering the front part of the tongue c) raising the back part of the tongue d) lowering the jaw with additional lip rounding 6. Production of the phoneme /a/ in English requires a) raising the front part of the tongue b) lowering the front part of the tongue c) raising the back part of the tongue d) lowering the jaw and the tongue. 7. What structure refers to the throat? a) Pharynx b) Oral cavity c) Vocal tract d) Epiglottis e) Nasal cavity 8. During sustained articulation for a whispered vowel, a) abductor and adductor muscles alternately contract to open and close the glottis b) contraction of abductor muscles is sustained throughout the vowel 3

4 c) contraction of adductor muscles is sustained throughout the vowel d) neither abductor nor adductor muscles is contracted 9. Which of the following is TRUE? a) The principal vocal organs include the lungs, the trachea, the larynx, the pharynx, the nose, the jaw, the tongue, and the mouth. b) The fundamental frequency is controlled by the mass, length and tension of the vocal tract. c) The vocal tract consists of the pharyngeal cavity and the oral cavity, but not the nasal cavity. d) Vocal organs are solely devoted to speech production. 10. Which of the following statements is TRUE? a) Stops, fricatives, approximants and nasals differ from each other in place of articulation. b) One main difference between consonants and vowels lies in articulatory constriction. c) Consonants are typically longer in duration and higher in energy than vowels. d) Whispered speech can be understood because it carries the f0 and formant information. 11. Which of the following intrinsic laryngeal muscles compose the main body of the vocal folds? a) cricothyroid b) posterior cricoarytenoid c) interarytenoids d) thyroarytenoid 12. The amplitudes of the harmonics with increasing frequency in the spectrum for the buzz sound produced by the vocal folds. a) decrease b) increase c) remain unchanged d) saturate 13. If formant frequencies of a vowel are held constant but its fo changes appropriately, a) the vowel will remain the same, but perceived pitch will change b) the perceived pitch will remain the same, but the vowel will change c) both perceived pitch and the vowel will change d) neither the perceived pitch nor the vowel will change 14. When the sound wave produced by the vibrating vocal folds excites the air-filled vocal tract, a) the frequencies of the harmonics are changed b) the amplitudes of the harmonics are changed c) the amplitudes and frequencies of the harmonics are changed d) neither the amplitudes nor the frequencies of the harmonics are changed 15. The resonant frequencies of the vocal tract are determined by a) the amplitude of vocal fold vibration b) the frequency of vocal fold vibration c) the amplitude and frequency of vocal fold vibration d) the size and shape of the vocal tract e) None of the above. 16. What class of speech sounds is produced when the vocal folds remain abducted and turbulence is created at the point of constriction within the vocal tract? a) voiced fricatives b) vowel plosives c) voiceless fricatives d) voiced affricates 4

5 17. Suppose a given vowel has f0 = 100 Hz, F1 = 405 Hz, F2 = 2002 Hz. a) The two lowest resonances in the vocal tract are close to the 4 th and 20 th harmonics. b) The resonances in the vocal tract have only two components: F1 and F2. c) This vowel cannot exist because the fundamental frequency = F2 F1 = 1600 Hz. d) According to Fourier analysis, this vowel has exactly three sinewave components at 100 Hz, 400 Hz, and 2000 Hz. 18. Voice, as we know it, results from three components: voiced sound, resonance, and articulation. Which of the following is TRUE? a) Voiced sound is amplified and modified by the vocal tract resonators. b) Vibratory Cycle in vocal folds = Open + Close Phase c) Breakdowns can happen to the air pressure system, the vibratory system, and the resonating system, creating various voice disorder symptoms. d) All of the above. Chapter 5 1. Which of the following is a unit of measurement for loudness? a) db SPL b) Sone c) Hz d) Mel e) db IL 2. The three bones in the middle ear are. a) meatus, incus, and stapes b) scala vestibuli, scala media, and scala tympani c) cricoid, thyroid, and arytenoid d) malleus, incus, and stapes e) outer bone, middle bone, inner bone 3. Which of the following is TRUE? a) Minimum audibility = absolute threshold of hearing b) 1 db SPL = 1 sone c) 1 db SPL = 1 phon d) 1 Hz = 1 mel e) 1 sone = 1 phon 4. Which of the following is FALSE? a) The amount of masking depends on the intensity, spectrum and temporal characteristics of the masker. b) When the intensity of the sound gets stronger on the right ear, the perceived auditory image moves to the right ear. c) Auditory localization in space is accomplished by resolving interaural intensity and time differences. d) A signal with frequency components of 240 Hz, 360 Hz, 480 Hz, and 600 Hz has a fundamental frequency of 240 Hz. 5. The waveform of a sound signal displays a) amplitude, frequency, and duration b) amplitude as a function of time c) frequency as a function of time d) amplitude as a function of frequency e) frequency and amplitude as a function of time 5

6 6. When a sound wave sets the tympanic membrane into vibration, the membrane vibrates a) independently of the frequency of the sound wave b) at the natural frequency of the tympanic membrane c) at a frequency determined by the mass and stiffness of the tympanic membrane d) at the frequency of the applied force 7. A major function of the middle ear is to a) maintain equilibrium and balance. b) keep infections contained so that the inner ear will not be contaminated. c) serve as an amplifier. d) cause the tympanic membrane to vibrate. 8. The hair cells inside the Organ of Corti are located on. a) tympanic membrane b) basilar membrane c) tectorial membrane d) Reissner s membrane e) diaphragm membrane 9. The amplitude of the traveling wave on the basilar membrane for a sinusoid is a) greatest near the basal end for low frequencies b) greatest near the apical end for high frequencies c) greatest near the apical end for low frequencies d) approximately constant throughout its length e) independent of sound frequency 10. Neural potentials are generated in the auditory system when a) the tympanic membrane is forced inward b) shearing forces on the cilia of the hair cells stimulate nerve fibers c) the tectorial membrane rises to make contact with Reissner s membrane d) the outer hair cells move towards the inner hair cells e) sound reaches the brain 11. The minimum audibility curve, averaged for a large group of listeners with normal hearing, informs us that a) the auditory system is most sensitive in a mid-frequency range b) the auditory system is most sensitive for frequencies below 1000 Hz c) the auditory system is most sensitive for frequencies above 5000 Hz d) the auditory system is equally sensitive from 20 Hz to 20,000 Hz e) we cannot never hear a sound below 0 db 12. The unit of measure for perceived (or subjective) pitch is a) mel b) phon c) Hz d) sone 13. Auditory localization in space is accomplished by resolving a) interaural time differences and interaural intensity differences b) interaural intensive differences c) interaural time differences d) visual localization of the source of sound 14. When two identical sinusoids are presented binaurally to listeners under earphones, the listeners hear a single fused image within the cranium in the median plane. The image will move toward the left ear if a) the signal to the right ear lags the signal to the left ear 6

7 b) the intensity of the signal to the right is increased c) the signal to the right ear leads the signal to the left ear d) the intensity of the signal to the left remains the same 15. A signal is presented to a listener in the presence of a masking noise that fluctuates in intensity. The amount of masking that will be produced depends on a) the intensity of the masker b) the spectrum of the masker c) the temporal characteristics of the masker d) all of the above 16. A major function of the outer ear is to a) collect and carry sound to the middle ear. b) perform Fourier analysis on sounds. c) convert sound into nerve pulses. d) reduce the mechanical vibrations of a sound to protect the middle ear. 17. Which of the following is FALSE? a) The human inner ear is where sound waves are amplified by means of the vibrations of tiny bones. b) The Eustachian tube connects the middle ear and throat. c) In the cochlea, the hair cells are contained by the basilar membrane. d) The auditory pathway includes organ of corti, cochlea nerve, spiral ganglion, cochlea nucleus, superior olive, inferior colliculus, and auditory cortex. 18. Which of the following factor(s) can contribute to hearing loss? a) head injury b) listening to very loud music and sounds, especially through headphones c) ototoxic medication d) All of the above Answers Chapter 9 1. b 2. b. 3. c 4. d 5. c 6. c 7. b 8. d 9. b. 10. a 11. a 12. d 13. c 14.e 15. b 16. a Chapter 4 1.c 2. b 3. b 4. d 5. c 6. d 7. a 8. b 9. a 10. b 11. d 12. a 13. a 14. b 15. d 16. c 17. a 18.d Chapter 5 1.b 2. d 3. a 4. d 5. b 6. d 7. c 8. b 9. b 10. b 11. a 12. a 13. a 14. a 15. d 16. a 17. a 18.d 7